Telephone system.



P. GLAUSENL TELEPHONE SYSTEM.

APPLICATION FILED JULY 18,1903.

1 1118111911 Sept. 5,1911.

0.. WASHINGTON. 11.4..

STATES AT FTQ.

HENRY P. CLAUSEN, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS,T0

STROMBERGr-CARLSON TELEPHONE MANUFACTURING COMPANY, OF ROCHESTER NEV fYORK, A CORPORATION OF NEW YORK.

TELEPHONE SYSTEM.

Specification of Letters Patent.

Patented Sept. 5, 1911.

Tb all whom it may concern:

Be it known that I, HENRY P. CLAUsnN, a citizen of the United States ofAmerica, and resident of Chicago, Cook county, Illinois, have invented acertain new and useful Improvement in Telephone Systems, of which thefollowing is a specification.

My invention relates to telephone systems in which the current forsignaling purposes is supplied from a battery or other source at thecentral station, and preferably to systems in which the current fortalking purposes is also supplied from a common battery or centralizedsource of supply. In systems of this character, the subscribers linesusually terminate in what are called spring-jacks, these spring-jacksbeing located on the switchboards at the central station; and theconnections are established by the operators through the medium of whatare called plugs and cord-circuits. Said plugs are usually arranged inpairs, one at each end of a flexible conductor composed of two or morestrands, and when inserted in spring-jacks a pair of these plugs and theconnecting cords are adapted to establish a talking circuit between thesubscribers lines to which said jacks are allotted. It is also customaryto provide the switchboard apparatus with what are called line andsupervisory signals, the line signals enabling the subscribers tocall-in and attract the attention of the operator, when a connection isdesired, and the supervisory signals enabling the subscribers toindicate when they are through talking. In systems of this character, itis also preferable to employ complete metallic line connection betweenthe sub-stations and the exchange or central station.

Generally stated, the object of my invention is to provide an improved,simplified, and highly efficient telephone system of the foregoingcharacter.

A special object is to provide an improved arrangement whereby the lineand supervisory signals may be controlled and operated in accordancewith approved methods of practice, and without the necessity ofemploying relays or other similar devices in the cord-circuits.

It is also an object to provide certain details and features ofimprovement tending to lncrease the general efliciency of a telephonesystem of this particular character.

To the foregoing and other useful ends, my invention consists in mattershereinafter set forth and claimed.

The accompanying drawing is a diagram illustrating the construction andcircuit arrangement of a telephone system embodying the principles of myinvention, only two substations and a single cord-circuit being shown,and it being understood, however, that the system may comprise as manysubstations as is desirable or necessary, and that it may also compriseas many operators cord-circuits as may be found convenient or expedient.

As thus illustrated, my improved central energy or common batterytelephone system comprises a couple of substations A, B, having completemetallic line connection with the switchboard apparatus at the centralstation. The line of substation A terminates in a spring-jack C, whilethe line of substation D terminates in a spring-jack D, both jacks beinglocated on either the same or different sections or divisions of theswitchboard at the exchange or central station. An operatorscord-circuit E, provided with answering and calling plugs F and G, isprovided and employed as a medium for establishing electrical connectionbetween the said jacks, and for thereby establishing a through talkingcircuit between the substations. A line signal H is associated with thejack 0, so as to enable the subscriber at substation A to call-in andattract the at tention of the operator; and a similar line signal I,associated with the jack D, enables the subscriber at substation B toreceive attention from the operator. The supervisory signals J and K areassociated, respectively, with the said answering and calling plugs, andthe arrangement, as will hereinafter more fully appear, is such that thesignal J is displayed when the subscriber at substa tion B hangs up hisreceiver. In a similar manner, the signal K is displayed when thesubscriber at substation A hangs up his receiver. In order that she mayconverse with subscribers, the operator is provided with a talking setL, adapted to be bridged across the cord-circuit. The generator h/I,which is also adapted to be bridged across the cordcircuit, enables theoperator to ring the bells at the subscribers stations. The functions ofthe relays N, O, and P, Q, will be more readily understood from anexplanation of the manner in which connection is established between thetwo substations.

Suppose, for example, that the subscriber at substation B desires tocommunicate with the subscriber at substation A. In such case thesubscriber B takes down his receiver Z2, and by so doing releases theswitch-hook b, and thereby closes a line circuit from the common batteryor centralized source of current R, through the battery lead 1, througha coil 2 of the line relay P, through the conductor 3, thence throughthe limb or line conductor 4, through the transmitter 5, through thecontact point 6, through one coil 7 of the inductive connection betweenthe receiver and the line circuit, through the other limb or lineconductor 8, through the conductor 9, thence through the other coil 10of said line relay, and through the other battery lead 11 to saidbattery. The windings of said line relay P are such that the currentflowing through this completed line circuit energizes the said relay andcauses it to attract its armature. WVhen attracted,the said armaturecloses a circuit from the said battery, through the battery lead 1,through the impedance coil 12, or other suitable resistance, through theconductor 13, through the said armature 14;, through contact 15, thencethrough the line lamp signal I, through the conductor 16, through thecontact 17, and the armature 18, and thence through the battery lead 11to said battery. The resistance of this circuit is such that sufficientcurrent flows therein to cause the lamp I to glow. This attracts theattention of the operator, who thereupon inserts the answering-plug F inthe spring-jack D. This act on the part of the operator establishes aderived circuit from the battery B through the battery lead 1, throughthe resistance 12 and the coil of the relay Q, through the conductor 19,through the testing ring 20 of said jack, through the sleeve contact 21of said plug, thence through the supervisory lamp signal J, and throughthe ground or common connections 22 and 23 to said battery. Suflicientcurrent flows through this derived circuit to energize the relay Q,which is in the nature of a cut-off relay, and to cause it to attractits armature 18. When thus attracted, the armature 18 opens the abovedescribed local circuit of the line lamp signal I, thereby cutting offthe battery from this lamp and causing it to cease glowing. But thecurrent flowing through this derived circuit, owing to the resistance ofthe relay Q, is not suflicient to cause the lamp J to glow. Thus theoperator answers the call, and in so doing automatically restores theline or calling signal, to its normal condition. Upon receiving theorder for connection from subscriber B, which she does by pressing herlistening key 24, so as to bridge her talking set across thecord-circuit, the operator then inserts the calling plug G in the jackC. The insertion of the calling plug in this manner completes a derivedcircuit from the battery R,through the battery lead 25, through theimpedance coil or other suitable resistances 26, through the coil of thecut-oil relay 0, thence through the conductor 27, through the testingring 28 of the jack C, through the sleeve contact 29 of said callingplug, thence through the lamp K, and through the ground or commonconnections 30 and 23 to said battery. It will also be observed thatthis derived circuit includes the armature 31 and the contact 32, whichare so arranged as to constitute a normally closed shunt around the coilof the cut-off relay 0. As this shunt is of low resistance, the relay 0consequently remains deenergized, while at the same time sufficientcurrent flows through the derived circuit to cause the lamp K to glow.This lamp, as will hereinafter more fully appear, continues to glowuntil the salled subscriber answers the call. The operator now pressesher ringing key 33,so as to bridgethe genera-' tor across thecord-circuit, and so as to thereby project ringing current on to theline leading to substation A. This rings the bell at substation A, andsubscriber A, in answering the call, takes down his receivera, therebyreleasing the switch-hook a. In rising, the switch-hook closes a linecircuit from the battery R, through the battery lead 25, through thecoil 3st of the line relay N, thence through thelimb or line conductor35, through the subscribers transmitter 36, through the switch-hook aand the contact 37, through the coil 38 of the inductive con nectionbetween the receiver A and the line circuit, thence through the, otherlimb or line conductor 39, through the other coil 10 of the said linerelay N, and through the battery-lead 4:1 to said battery. The windingsof the relay N are such that the closing of this line circuit causessaid relay to atwith the contact as, but this does not cause the lamp Hto glow, as previously stated, inasmuch as the relay 0 has alreadyopened the circuit of the lamp. The through talking circuit thusestablished between the two subscribers, comprises, it will be seen, thelimbs of the two lines, the jack and plug contacts, and the talkingstrands 45 and 46 of the cord-circuit. Preferably, these talking strandsare provided, respectively, with condensers 47 and 48 to stop the How ofbattery current. hen the subscriber B hangs up his receiver, and therebyopens the line circuit, the relay P becomes deenergized, therebyallowing its armature 14 to engage the contact 49, and in so doing toclose a low resistance shunt around the cut-off relay Q. The resistanceof the circuit of the lamp J being thus reduced, said lamp is therebycaused to glow, and to, in this way, indicate to the operator thatsubscriber B is through talking. In a similar manner, subscriber A,

in hanging up his receiver, opens the line circuit, deenergizes therelay N, and closes a shunt around the cut-off relay 0, which results,of course, in a sufiicient reduction of the resistance in the circuit oflamp K to cause the latter to glow. The operator then withdraws theplugs and in so doing restores the system to its normal condition, atleast so far as these two particular substations and this particularcord-circuit are concerned.

It will be seen that the relays N and P, by having their coils locatedin opposite sides of the line circuit, balance the circuit, and act asimpedance or retardation to pre vent the passage of voice currents. Itwill also be seen that the relays N and O are employed to conjointlycontrol the circuit of the lamp H, and that the relay N is adapted tocontrol the circuit of the supervisory lamp K. The relay N and the jack0 and the plug G are adapted to conjointly control the circuit of thelamp K. In a similar manner, it will be seen that the relays P and Qhave a conjoint control over the circuit of lamp J, and that the relay Pis adapted, independently of any other relay, tocontrol the circuit ofthe lamp J. Also, the relay P and the jack D and the plug F are adaptedto conjointly control the circuit of the relay J. Again, my improvedsystem, as will be observed, comprises line relays adapted to controlnormally closed shunts around cut-oft relays.

It will be readily understood that the resistances for the variousrelays and coils and the capacities of the condensers can be adjusted tosuit varying conditions, and can be of any suitable or desiredcharacter. It will also be understood that the various instruments,devices, etc, employed in the system can be of any suitable, known, orap-v proved construction. With my improved circuit arrangement, however,it will be seen that a very small amount of current is required forclearing the line signals.

I claim as my invention l. A telephone system comprising a subscribersline, a line signal and a supervisory signal, a centralized source ofcurrent sup ply, a line relay and a cut-oil? relay, said relays beingadapted to conjointly control said line signal, the said supervisorysignal being included in the energizing circuit of the cutoff relay andsaid line relay being adapted to control the said supervisory sig nal,by shunting the resistance of the cutoff relay.

2. A telephone system comprising a subscribers line, line andsupervisory signals, a central source of current supply, a line relayand a cut-off relay, said relays being adapted to conjointly control thesaid line signal, the line relay being adapted to control the saidsupervisory signal, by shunting the resistance of the cut-off relay, anda coil of the-cut-oflf relay being adapted to act as resistance toprevent the display of said supervisory signal until the line relay isdeenergized.

3. A telephone system comprising a subscribers line, line andsupervisory signals, line and cut-cit relays, a central source ofcurrent supply, a normally closed shunt around the coil of said cut-oifrelay, said shunt being included in the circuit of said supervisorysignal, said relays being adapted to conjointly control the said linesignal, and said line relay being adapted to control said shunt.

a. A telephone system comprising a subscribers line, line andsupervisory signals, a central source of current supply, a jackconnected with said line, an operators cordcircuit plug connected withsaid supervisory signal, and line and cut-off relays, said relays beingadapted to conjointly control said line signal, and said line relay andsaid plug and jack being adapted to conjointly control said supervisorysignal, and an artificial resistance adapted to be included in andexcluded from the circuit of said supervisory signal in the control ofsaid signal.

5. A telephone system comprising a pair of subscribers lines, asubscribers switchhook for each line, a central source of current supplyconnected with said lines, line and supervisory signals, a jackconnected with each line, an operators cord-circuit provided with plugsadapted for insertion in said jacks, line and cut-off relays for eachline, a normally closed shunt around the coil of each cut-oft relay, theline and cut-ofi' relays of each line being adapted to conjointlycontrol the line signal allotted to said line, each line relay beingadapted to control the shunt about the associated cut-0E relay, and saidline relay thereby being adapted to cooperate with said jacks and plugsin conjointly controlling the said supervisory sig nals.

6. A telephone system comprising a subscribers line, a central source ofsupply, a jack connected With the line, an operators cord-circuit plug,a line signal, a local circuit for said line signal including saidbattery, and including also a normally closed and a normally openswitch-point, a supervisory signal connected with the plug, a localcircuit for said supervisory signal including said battery and includingalso said plug and jack and normally closed switchpoint, a line relayadapted to controlthe normally closed switch-point of said supervisorysignal, and also the normally open switch-point of said line signal, anda normally short circuited cut-oii relay adapted to control the normallyclosed switch-point of said line signal.

7. A telephone system comprising a subscribers line, line andsupervisory signals, a line relay and a normally short circuited cut-oftrelay adapted to conjointly control the circuit of said line signal,each relay being adapted to control a switch-point in the circuit ofsaid line-signal, and a central source of current supply, saidsupervisory signal being adapted to constitute part of the energizingcircuit of said cut-off relay.

8. A telephone system comprising a subscribers line, a line signal, acentral source of current supply, a normally short circuited cut-oftrelay, and a supervisory signal, the coil of said cut-ofi relay beingadapted to serve as resistance to prevent the display of saidsupervisory signal until the proper time.

9. A telephone system comprising a cutoff relay, a shunt normallyincluded about said relay, together with means for opening and closingsaid shunt, means to be cut oil by the energizing of said relay and abattery having one pole normally connected with one terminal of saidrelay, a lamp signal and a local circuit for energizing the cut-offrelay in series with said lamp signal.

10. A telephone system comprising a cutoff relay, a shunt for saidrelay, together with means for opening and closing said shunt, saidrelay and shunt being in a normally open circuit, means to be cut 0E bythe energizing of said relay, a supervisory lamp signal and a localcircuit for energizing said cutofi' relay in series with said lampsignal.

11. A telephone system comprising a cutoff relay, a lamp signal, anormally closed shunt around such cut-off relay, a battery, and anormally open circuit including said lamp signal and the coil of saidrelay in series together with means for opening and closing said shunt.

12. A telephone system comprising a relay and a lamp signal, the relaycontrolling the said lamp signal, and a normally open circuit includingsaid lamp signal for energizing the said relay, and a normally opencircuit excluding the said relay for lighting the said lamp. m

13. In a telephone sy. em, a line, a line relay, a cut-ofi relay, and ashunt around the cut-off relay controlled by the line relay.

let. In a telephone system, a line, a line relay therefor, a cut-offrelay, and a normally closed shunt around the cut-off relay controlledby the line relay. 7

15. In a telephone system, a line, a line relay, and means forenergizing it during use of the line for conversational purposes, acut-off relay, and a low resistance shunt closed around the cut-offrelay by the deenergizing of the line relay.

16. In a telephone system, a line, a line relay, a cut-off relay, ashunt around the cutoff relay controlled by the line relay, and asupervisory lamp signal provided with a circuit which includes saidshunt.

17. In a telephone system, a line, a relay having one terminal thereofpermanently connected with the line, a normally closed shunt around saidrelay, means for opening said shunt, and a supervisory lamp signalprovided with a circuit which includes said shunt when the same isclosed.

18. In a telephone system, adouble Wound line relay, a normally closedshunt controlled thereby and a cut-oil relay associated therewith andincluded in said shunt, as stated.

19. In a telephone exchange system, the combination with a telephoneline extending from a substation to an exchange, of a line relay at theexchange, a source of current adapted to be closed through said linerelay through the agency of substation apparatus, cord connectingapparatus for connecting said line with another for conversation, acut-off relay included in a high resistance circuit controlled by thecord connecting apparatus, a line signal jointly controlled by said lineand cut-01f relays, a supervisory signal included in said highresistance circuit, and means whereby the deenerg'ization of said linerelay causes a short-circuiting of the resistance of the circuit throughsaid supervisory signal.

20. In a telephone exchange system, the combination with a telephoneline extending from a substation to an exchange, of a line relay at theexchange, a source of current adapted to be closed through said linerelay through the agency of substation apparatus, cord connectingapparatus for connecting said line with another for conversation, acut-off relay included in a high resistance circuit controlled by thecord connecting apparatus, a line signal in a local circuit includingthe armatures of said relays, the circuit through said line signal beingclosed when the line relay is energized and the cutoff relay isdeenergized, a supervisory signal included in said high resistancecircuit, and means whereby the deenergization of said line relay causesa short-circuiting of the resistance of the circuit through saidsupervisory signal.

21. A telephone exchange system including a telephone line extendingfrom a subscribers station to an exchange, a connecting switch inassociation with the telephone line,

a cord circuit for uniting telephone lines in conversation, a disconnectsignal device, a circuit therefor including a portion of the connectingswitch and the cooperating portion of a cord circuit in connectiontherewith when lines are united for conversation, a line relay inassociation with the telephone line controlled by the switchhook at thesubstation serving, when the telephone is upon its hook, to close anopening in said circuit, and, when the telephone is removed from itshook, to establish an opening in said circuit, and a cut-off relaybrought into the disconnect signal circuit by the energized line relay.

22. A telephone exchange system includ ing a telephone line extendingfrom a substation to an exchange, a connecting switch in associationwith the telephone line, a cord circuit for uniting telephone lines inconversation, a disconnect signal device, a cir cuit therefor includinga portion of the connecting switch and the cooperating portion of a cordcircuit in connection therewith when lines are united for conversation,a line relay in association with the telephone line controlled at thesubstation serving, when the telephone line is open at the substation,to close an opening in said circuit, and, when the telephone line isclosed at the substation, to establish an opening in said circuit, and acut-off relay brought into the discon nect signal circuit by theenergized line relay.

23. A telephone exchange system including a telephone line extendingfrom a subscribers station to an exchange, a jack for the telephoneline, a cord circuit for uniting telephone lines in conversation, adisconnect signal device, a circuit therefor including a portion of thejack and the cooperating plug of a cord circuit in connection therewithwhen lines are united for conversation, a line relay in association withthe telephone line controlled by the switch-hook at the substationserving, when the telephone is upon its hook, to close an opening insaid circuit, and, when the telephone is removed from its hook, toestablish an opening in said circuit, and a cut-off relay brought intothe disconnect signal circuit by the energized line relay.

24:. A telephone exchange system including atelephone line extendingfrom a substation to an exchange, a jack for the telephone line, a cordcircuit for uniting telephone lines in conversation, a disconnect slgnaldevice, a circuit therefor including a portion of the jack and thecooperating port1on of a cord circuit in connection therewith when linesare united for conversation. a line relay in association with thetelephone line controlled at the substation serving. when the telephoneline is open at the substation, to close an opening in said circuit,and, when the telephone line is closed at the substation, circuit, and acut-0H relay brought into the disconnect signal circuit by the energizedline relay.

25 111 a telephone exchange system, the combination with a telephoneline extending from a substation to an exchange, of a line relay at theexchange, a source of current adapted to be closed through said linerelav through the agency of substation apparatus, cord connectingapparatus for connecting said line with another for conversation, acut-oii relay included in a high resistance circuit controlled by thecord connecting apparatus, a line signal jointly controlled by said lineand cut-oft relays, the line signal being connected between the frontcontact of the line relay and the back contact of the cut-ofi relay,whereby said line signal has no permanent connection with said sourceor" current, a supervisory signal included in said high resistancecircuit, and means whereby the deenergization of said line relay causesa short-circuiting of the resistance of the circuit through saidsupervisory signal.

26. In a telephone exchange system, the combination with a telephoneline extending from a substation to an exchange, of a line relay at theexchange, a source of current adapted to be closed through said linerelay through the agency of substation apparatus, cord connectingapparatus for connecting said line with another for conversation, acutoff relay included in a high resistance circuit controlled by thecord connecting apparatus, a line signal in a local circuit includingthe armatures of said relays, the line signal being connected betweenthe front contact of the line relay and the back contact of the cut-ofirelay, whereby said line signal has no permanent connection with saidsource of current, the circuit through said line signal being closedwhen the line relay is energized and the cut-off relay is deenergized, asupervisory signal included in said high resistance circuit, and meanswhereby the de'energization of said line relay causes a short-circuitingof the resistance of the circuit through said supervisory signal.

27. A telephone exchange system including a telephone line extendingfrom a subscribers station to an exchange, a connecting switch inassociation with the telephone line,

to establish an opening in said a cord circuit for uniting telephonelines in conversation, a disconnect signal device, a circuit thereforincluding a portion of the connecting switch and the cooperating portionof a cord circuit in connection therewith when lines are united forconversation, a line relay in association with the telephone linecontrolled by the switch-hook at the substation serving, when thetelephone is upon its hook, to close an opening in said circuit, and,when the telephone is removed from its hook, to establish an opening insaid circuit, and a cut-off relay brought into the disconnect signalcircuit by the energized line relay, the line signal being connectedbetween the front contact of the line relay and the back contact of thecut-elf relay, whereby said line signal has no permanent connection withsaid source of current.

28. A telephone exchange system including a telephone line extendingfrom a substation to an exchange, a connecting switch in associationwith the telephone line, a cord circuit for uniting telephone lines inconversation, a disconnect signal device, a circuit therefor including aportion of the connecting switch and the cooperating portion of a cordcircuit in connection therewith when lines are united for conversation,a line relay in association with the telephone line controlled at thesubstation serving, when the telephone line is open at the substation,to close an opening in said circuit, and, when the telephone line isclosed at the substation, to establish an opening in said circuit, and acut-ofi' relay brought into the disconnect signal circuit by theenergized.

line relay, the line signal being connected between the front contact ofthe line relay and the back contact of the cut-off relay, whereby saidline signal has no permanent connection with said source of current.

29. A telephone exchange system including a telephone line extendingfrom a subscrlbers station to an exchange, a ack for the telephone l1ne,a cord circuit for unitlng telephone lines in conversation, a disconnectsignal device, a circuit therefor including a portion of the jack andthe cooperating plug of a cord circuit in connection therewith whenlines are united for conversation, a line relay in association with thetelephone line controlled by the switch-hook at the substation serving,when the telephone is upon its hook, to close an opening in saidcircuit,

and, when the telephone is removed from its hook, to establish anopening in said circuit, and a cut-off relay brought into the disconnectsignal circuit by the energized line relay, the line signal beingconnected between the front contact of the line relay H and the backcontact of the cut-oft relay,

whereby said line signal has no permanent connection with said source ofcurrent.

30. A telephone exchange system including a telephone line extendingfrom a substation to an exchange, a jack for the telephone line, a cordcircuit for uniting telephone lines in conversation, a disconnect signaldevice, a circuit therefor including a portion of the jack and thecooperating po'rtion of a cord circuit in connection therewith whenlines are united for conversation, a line relay in association with thetelephone line controlled at the substation serving, when the telephoneline is open at the sub station, to close an opening in said circuit,and, when the telephone line is closed at the substation, to establishan opening in said circuit, and a cut-off relay brought into thedisconnect signal circuit by the energized line relay, the line signalbeing connected between the front contact of the line relay and'the backcontact of the cut-off relay, whereby said line signal has no permanentconnection with said source of current. I

Signed by me at Chicago, Cook county, Illinois, this 13th day of July,1908.

HENRY P. CLAUSEN. 3

Witnesses:

ARTHUR F. DURAND, 7M. A. HAnDERs.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents. Washington, D. 0'.

